Why does white snow melt faster than dirty snow?

Answers

Two reasons, I believe: the first, that white snow reflects better than dirty snow and so it melts faster because of the heat from reflecting the sun. Second, if the snow is dirty then there are more particles and kinds of matter in it than white snow, which is mostly water and has no inhibitors.

Actually, dirty snow is darker and therefore abosrbs more heat causeing it to melt and release the polutants that caused it to become dark. This is a particularly significant problem in artic areas with large snow land masses.

“The effect is more conspicuous in Arctic areas, where Zender believes that more than 90 percent of the warming could be attributed to dirty snow. “When we inject dirty particles into the atmosphere and they fall onto snow, the net effect is we warm the polar latitudes,” said Zender. “Dark soot can heat up quickly. It’s like placing tiny toaster ovens into the snow pack.””

Though there are several reasons this may appear to be the case, “dirty” snow actually melts faster because the dark particulate matter absorbs light, which is converted to heat, increasing the rate of melting of the surrounding snow. Two reasons this may not seem to be what’s going on are that dirty snow has often been plowed or shoveled, so its denser than the surrounding, untouched snow, and as the snow melts and evaporates the dirt concentrates, making the remaining piles of snow look dirtier and dirtier.